A. Field of the Invention
This invention relates to bituminous concrete surfaces in general and in particular to a new method for reconditioning existing bituminous concrete pavement and simultaneously resurfacing it with a non-skid, light-reflecting material.
B. Description of the Prior Art
It is a well-known fact that asphalt and tar generally tend to lose their shiny black surfaces and turn a dull grey color in time. This is due to the oxidation and weathering of the bituminous concrete, a natural process which robs the bituminous cement of its residual oils. Loss of these oils gradually causes the pavement to turn hard and brittle, and soon leads to the appearance of cracks and the eventual disintegration of the bituminous surface.
Since this development in the pavement is undesirable, various repair techniques have been employed by the construction industry to counteract the pavement deterioration. The standard one consists of the following five-step procedure:
(1) CLEANING THE TOP SURFACE OF THE PAVEMENT TO REMOVE ALL FOREIGN MATTER;
(2) FILLING ALL CRACKS WITH CRACK-FILLER CEMENTS;
(3) RAISING ALL UTILITY TERMINALS AND CURBING TO THE HEIGHT OF THE NEW RESURFACING GRADES;
(4) PLACING A TACK COAT OF HOT OR COLD BITUMINOUS LIQUID ON THE OLD PAVEMENT; AND
(5) SWELLING AND RESURFACING THE OLD PAVEMENT WITH A NEW LAYER OR LAYERS OF BITUMINOUS CONCRETE.
While this conventional repair technique is effective, there are a number of problems associated with it. First, this procedure is quite expensive in terms of manpower and materials. Second, since these repairs require a good deal of time to accomplish and since the pavement must be closed to traffic during the period of repair, this procedure often means extensive traffic detours and user inconvenience. Third, because these repairs must take place every five to ten years in a typical environment and even more often in an inclement one, layer after layer of bituminous concrete is deposited on the roadbed with time, with the newer surfaces being laid down on top of the older ones. This means that each time a new layer of bituminous concrete is added, all existing utility terminals and curbing must be raised to the height of the new surface. Furthermore, the level of the pavement eventually rises so high as to surpass the level of the surrounding terrain. When this occurs, all the bituminous surfacing must be torn out down to the level of the roadbed and the construction of the surfacing must be begun again. As might be expected, tearing out the accumulated layers of bituminous concrete is an expansive and time-consuming process.